Wired Doorbell no longer turns on

[kmwilcher]

Had wired doorbell installed and working. Had to remove it for 2-3 days to fabricate custom plate to mount on uneven stone wall. When I went to reconnect the doorbell the unit no longer lights up or connects. My voltage reads 18.8V and I've tried un-installing/re-installing both the doorbell and the chime unit multiple times. I've left the doorbell connected multiple days thinking maybe there's an internal battery that was drained and for some reason won't charge even though connected? 

[jguerdat]

Yes, there's an internal battery and it needs to charge before it will work again. When I did something similar, it seemed that a ~1 hour charge time was sufficient to get the doorbell to work. Could be less - I didn't try.